1. Field of the Invention
This invention relates to an apparatus for fabrication of a semiconductor device, more particularly, it relates to an apparatus using hybrid coupled plasma (HCP) having properties of inductively coupled plasma (ICP) and capacitively coupled plasma (CCP).
2. Discussion of the Related Art
As industry relating to semiconductor devices is developed, a fabricating apparatus of semiconductor devices having high capacity and high function has been researched. Accordingly, integration of much more number of elements in a limited area has been required. In addition, technology of ultra fine patterning and high integration has been researched and developed in fabrication field of semiconductor devices.
In order to obtain semiconductor devices having ultra fine patterning and high integration, a technology using plasma obtained by activating reaction gases has been widely used in a fabricating process of semiconductor devices. In the fabricating process of semiconductor devices, positive ions or radical of reaction gases in plasma state are used for depositing or etching a layer in a predetermined area of a substrate. A fabricating apparatus of semiconductor devices includes a chamber where plasma is formed. The chamber of the apparatus may be classified into a capacitively coupled plasma (CCP) type and an inductively coupled plasma (ICP) type according to a method of forming plasma.
FIG. 1 is a schematic view of an ICP type fabricating apparatus of a semiconductor device according to the related art. In FIG. 1, the ICP type fabricating apparatus includes a chamber 10 having an exhaust hole, a gas-injecting unit 20, an antenna 30 and an electrostatic chuck 60. Reaction gases are sprayed into the chamber 10 through the gas-injecting unit 20 and a source power is supplied to the antenna 30. A substrate “W” is loaded on the electrostatic chuck 60 where a bias power is supplied. In addition, a source radio frequency (RF) generator 50 and a source impedance matching box 40 are connected to the chamber 10. The source RF generator 50 supplies the source power to the antenna 30 and the source impedance matching box 40 matches a load impedance to a characteristic impedance of connection cables connected to the source RF generator 50. Moreover, a bias RF generator 80 and a bias impedance matching box 70 are connected to the electrostatic chuck 60. The bias RF generator 80 supplies the bias power to the electrostatic chuck 60 and the bias impedance matching box 70 matches a load impedance to a characteristic impedance of connection cables connected to the bias RF generator 80.
After the substrate “W” is disposed on the electrostatic chuck 60, the substrate “W” is fixed on the electrostatic chuck 60 by an electrostatic force. Then, the reaction gases are injected into the chamber 10. At the same time, the source power is supplied to the antenna 30 and the bias power is supplied to the electrostatic chuck 60. The reaction gases are activated by the source power and the bias power to form plasma “P.” Positive ions in the plasma “P” rush onto and collide with the substrate “W” to form or etch a layer.
An ICP type fabricating apparatus of a semiconductor device has high production yield and low probability of damaging a substrate because of high plasma density and low ion energy distribution. The plasma density, however, is uniform in a central portion of the chamber and is not uniform in a boundary portion of the chamber. As the substrate is enlarged, the uniformity difference in the central portion and the boundary portion may further deteriorate the reliability of fabrication process.
FIG. 2 is a schematic view of a CCP type fabricating apparatus of a semiconductor device according to the related art. In FIG. 2, the CCP type fabricating apparatus includes a chamber 12 having an exhaust hole, a gas-injecting unit 22, an upper electrode 32 of a plate shape and an electrostatic chuck 62 as a lower electrode. Reaction gases are sprayed into the chamber 12 through the gas-injecting unit 22 and a source power is supplied to the upper electrode 32. A substrate “W” is loaded on the electrostatic chuck 62 where a bias power is supplied. In addition, a source RF generator 52 and a source impedance matching box 42 are connected to the chamber 12. The source RF generator 52 supplies the source power to the upper electrode 32 and the source impedance matching box 42 matches a load impedance to a characteristic impedance of connection cables connected to the source RF generator 52. Moreover, a bias RF generator 82 and a bias impedance matching box 72 are connected to the electrostatic chuck 62. The bias RF generator 82 supplies the bias power to the electrostatic chuck 62 and the bias impedance matching box 72 matches a load impedance to a characteristic impedance of connection cables connected to the bias RF generator 82.
After the substrate “W” is disposed on the electrostatic chuck 62, the chamber 12 is evacuated and the reaction gases are injected into the chamber 12. Then, an electric field is generated between the upper electrode 32 and the electrostatic chuck 62 by applying the source RF power and the bias RF power to the upper electrode 32 and the electrostatic chuck 62, respectively.
In a CCP type fabricating apparatus of a semiconductor device, ions produced by the high intensity electric field are used for an etching process because the ions have high energy. However, the ions can not be used for a chemical vapor deposition (CVD) process and a sputtering process under a low pressure because of their high energy. Specifically, since plasma produced in a CCP type apparatus has high sheath voltage, high self bias and high plasma impedance, the plasma may further deteriorate a substrate.